以Pd/C为催化剂,在改进的动力学实验装置上研究了松脂分子间氢转移反应的集总动力学.在消除内、外扩散影响的条件下,在线跟踪反应产物并用气相色谱法测定反应体系组成随时间的变化,构造了Pd/C催化剂上松脂分子间氢转移集总反应网络,建立了包含单萜烯、枞酸型树脂酸、海松酸型树脂酸、对伞花烃、氢化单萜烯、脱氢枞酸、氢化枞酸型树脂酸和氢化海松酸型树脂酸等复杂反应体系的集总动力学模型,并估算了模型参数.松脂单萜烯和树脂酸的反应级数分别为1和2,并得到了松脂分子间氢转移中各反应过程的活化能.结果表明,所建动力学模型与实验数据吻合良好,并能预测反应在533K下的集总组分浓度分布.Pd/C催化松脂分子间氢转移反应以脱氢反应为主,树脂酸的氢转移速率大于单萜烯的氢转移速率.
Using a novel experimental apparatus with an improved agitator, a lumped kinetic model for the intermolecular hydrogen transfer reaction of pine gum over a Pd/C catalyst was investigated under nitrogen atmosphere. The component concentrations were acquired by tracking analysis by gas chromatography. The lumped components of the complex reaction systems were defined and the reaction network was proposed. The lumped kinetic model of monoterpene, abietic type resin acid, pimaric acid type resin acid, p-cymene, hydro-monoterpene, dehydro-abietic acid, hydro-abietic type resin acid, and hydro-pimaric acid type resin acid was established based on the structural groups and approximate reaction kinetic theory according to the fundamental principles of the lumped method. The reaction orders of monoterpene and resin acid were 1 and 2, respectively. The kinetic model parameters were estimated and the activation energy was calculated for various reactions of the lumped kinetic model. The lumping model could characterize the kinetic behavior of the complicated reaction system and predict the reactant-product concentrations at 533 K. The dehydrogenation was the main reaction during the intermolecular hydrogen transfer reaction of pine gum, and the reaction rate of the resin acids was greater than that of monoterpene.